Sorry to hear that you had problems instalingl the new alum. valley cover. As I mentioned in my above post, installation problems are most likely to come up with most non blueprinted engines. It's not the fault of the new pan, it's the misalignment in most engine's geometry. The flexing stock steel pan can perfectly compensate in most cases.
Hope the elonguated bolt holes will do the trick for your engine. Do you have pics of your new alum. pan?

I read through the thread do these valley pans fit all years of the "MEL" such as (1958-1959)-(1960-196?)

If so, I'm interested in one of these valley pans.

Sort of yes sort of no. Right now we are waiting on Moon, who has already reoffered earlier this year their sharp valve covers for the 430's. Moon offered a valley cover once upon a time and it's even shown in the 97 catalog after new ownership took place BUT they are still looking for the mold. Until I get a definite answer from Moon, that they can not locate the old mold, or are absolutely not interested in recasting a new one, I'm not approaching any other company. I hope they have found it. I've already told them that they could sell more valley covers than they did of the valve covers as many of us on here would buy multiple pieces of the same part, just to get the wheels rolling again. I'm contacting Moon in Dec.